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Full-Text Articles in Physical Sciences and Mathematics
Enzymatic Electrochemical Biosensors For Neurotransmitters Detection: Recent Achievements And Trends, Zina Fredj, Baljit Singh Dr., Mohamed Bahri, Peiwu Qin, Mohamad Sawan
Enzymatic Electrochemical Biosensors For Neurotransmitters Detection: Recent Achievements And Trends, Zina Fredj, Baljit Singh Dr., Mohamed Bahri, Peiwu Qin, Mohamad Sawan
Articles
Neurotransmitters (NTs) play a crucial role in regulating the behavioral and physiological functions of the nervous system. Imbalances in the concentrations of NT have been directly linked to various neurological diseases (e.g., Parkinson’s, Huntington’s, and Alzheimer’s disease), in addition to multiple psychotic disorders such as schizophrenia, depression, dementia, and other neurodegenerative disorders. Hence, the rapid and real-time monitoring of the NTs is of utmost importance in comprehending neurological functions and identifying disorders. Among different sensing techniques, electrochemical biosensors have garnered significant interest due to their ability to deliver fast results, compatibility for miniaturization and portability, high sensitivity, and good controllability. …
Cardiac Inflammation, Oxidative Stress, Nrf2 Expression, And Coagulation Events In Mice With Experimental Chronic Kidney Disease, Abderrahim Nemmar, Suhail Al-Salam, Sumaya Beegam, Nur Elena Zaaba, Javed Yasin, Naserddine Hamadi, Badreldin H. Ali
Cardiac Inflammation, Oxidative Stress, Nrf2 Expression, And Coagulation Events In Mice With Experimental Chronic Kidney Disease, Abderrahim Nemmar, Suhail Al-Salam, Sumaya Beegam, Nur Elena Zaaba, Javed Yasin, Naserddine Hamadi, Badreldin H. Ali
All Works
Chronic kidney disease (CKD) is known to be associated with cardiovascular dysfunction. Dietary adenine intake in mice is also known to induce CKD. However, in this experimental model, the mechanisms underlying the cardiotoxicity and coagulation disturbances are not fully understood. Here, we evaluated cardiac inflammation, oxidative stress, DNA damage, and coagulation events in mice with adenine (0.2% w/w in feed for 4 weeks)-induced CKD. Control mice were fed with normal chow for the same duration. Adenine increased water intake, urine output, relative kidney weight, the plasma concentrations of urea and creatinine, and the urinary concentrations of kidney injury molecule-1 and …
In-Situ-Investigation Of Enzyme Immobilization On Polymer Brushes, Meike Koenig, Ulla König, Klaus-Jochen Eichhorn, Martin Muller, Manfred Stamm, Petra Uhlmann
In-Situ-Investigation Of Enzyme Immobilization On Polymer Brushes, Meike Koenig, Ulla König, Klaus-Jochen Eichhorn, Martin Muller, Manfred Stamm, Petra Uhlmann
Chemistry Department: Faculty Publications
Herein, we report on the use of a combined setup of quartz-crystal microbalance, with dissipation monitoring and spectroscopic ellipsometry, to comprehensively investigate the covalent immobilization of an enzyme to a polymer layer. All steps of the covalent reaction of the model enzyme glucose oxidase with the poly(acrylic acid) brush by carbodiimide chemistry, were monitored in-situ. Data were analyzed using optical and viscoelastic modeling. A nearly complete collapse of the polymer chains was found upon activation of the carboxylic acid groups with N-(3-Dimethylaminopropyl)-N′-ethylcarbodiimide and N-Hydroxysuccinimide. The reaction with the amine groups of the enzyme occurs simultaneously with re-hydration of the …
The Role Of Catalytic Residue PKA On The Hydrolysis/Transglycosylation Partition In Family 3 Β-Glucosidases, Inacrist Geronimo, Christina M. Payne, Mats Sandgren
The Role Of Catalytic Residue PKA On The Hydrolysis/Transglycosylation Partition In Family 3 Β-Glucosidases, Inacrist Geronimo, Christina M. Payne, Mats Sandgren
Chemical and Materials Engineering Faculty Publications
β-Glucosidases (βgls) primarily catalyze the hydrolysis of the terminal glycosidic bond at the non-reducing end of β-glucosides, although glycosidic bond synthesis (called transglycosylation) can also occur in the presence of another acceptor. In the final reaction step, the glucose product or another substrate competes with water for transfer to the glycosyl-enzyme intermediate. The factors governing the balance between the two pathways are not fully known; however, the involvement of ionizable residues in binding and catalysis suggests that their pKa may play a role. Through constant pH molecular dynamics simulations of a glycoside hydrolase Family 3 (GH3) βgl, we …
Interspecies Comparison Of Peptide Substrate Reporter Metabolism Using Compartment-Based Modeling [Post-Print], Allison Tierney, Nhat Pham, Kunwei Yang, Brooks Emerick, Michelle Kovarik
Interspecies Comparison Of Peptide Substrate Reporter Metabolism Using Compartment-Based Modeling [Post-Print], Allison Tierney, Nhat Pham, Kunwei Yang, Brooks Emerick, Michelle Kovarik
Faculty Scholarship
Peptide substrate reporters are fluorescently labeled peptides that can be acted upon by one or more enzymes of interest. Peptide substrates are readily synthesized and more easily separated than full-length protein substrates; however, they are often more rapidly degraded by peptidases. As a result, peptide reporters must be made resistant to proteolysis in order to study enzymes in intact cells and lysates. This is typically achieved by optimizing the reporter sequence in a single cell type or model organism, but studies of reporter stability in a variety of organisms are needed to establish the robustness and broader utility of these …
Structural Characterization Of A Newly Identified Component Of Α-Carboxysomes: The Aaa+ Domain Protein Csocbbq, Markus Sutter, Evan W. Roberts, Raul C. Gonzalez, Cassandra Bates, Salma Dawoud, Kimberly Landry, Gordon C. Cannon, Sabine Heinhorst, Cheryl A. Kerfeld
Structural Characterization Of A Newly Identified Component Of Α-Carboxysomes: The Aaa+ Domain Protein Csocbbq, Markus Sutter, Evan W. Roberts, Raul C. Gonzalez, Cassandra Bates, Salma Dawoud, Kimberly Landry, Gordon C. Cannon, Sabine Heinhorst, Cheryl A. Kerfeld
Faculty Publications
Carboxysomes are bacterial microcompartments that enhance carbon fixation by concentrating ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) and its substrate CO2 within a proteinaceous shell. They are found in all cyanobacteria, some purple photoautotrophs and many chemoautotrophic bacteria. Carboxysomes consist of a protein shell that encapsulates several hundred molecules of RuBisCO and contain carbonic anhydrase and other accessory proteins. Genes coding for carboxysome shell components and the encapsulated proteins are typically found together in an operon. The α-carboxysome operon is embedded in a cluster of additional, conserved genes that are presumably related to its function. In many chemoautotrophs, products of the expanded carboxysome …
Enzyme Localization, Crowding, And Buffers Collectively Modulate Diffusion-Influenced Signal Transduction: Insights From Continuum Diffusion Modeling, Peter M. Kekenes-Huskey, Changsun Eun, J. A. Mccammon
Enzyme Localization, Crowding, And Buffers Collectively Modulate Diffusion-Influenced Signal Transduction: Insights From Continuum Diffusion Modeling, Peter M. Kekenes-Huskey, Changsun Eun, J. A. Mccammon
Chemistry Faculty Publications
Biochemical reaction networks consisting of coupled enzymes connect substrate signaling events with biological function. Substrates involved in these reactions can be strongly influenced by diffusion “barriers” arising from impenetrable cellular structures and macromolecules, as well as interactions with biomolecules, especially within crowded environments. For diffusion-influenced reactions, the spatial organization of diffusion barriers arising from intracellular structures, non-specific crowders, and specific-binders (buffers) strongly controls the temporal and spatial reaction kinetics. In this study, we use two prototypical biochemical reactions, a Goodwin oscillator, and a reaction with a periodic source/sink term to examine how a diffusion barrier that partitions substrates controls reaction …
The Dimerization Domain In Dape Enzymes Is Required For Catalysis, Boguslaw Nocek, Anna Starus, Magdalena Makowska-Grzyska, Blanca Gutierrez, Stephen Sanchez, Robert Jedrzejczak, Jamey C. Mack, Kenneth W. Olsen, Andrzej Joachimiak, Richard C. Holz
The Dimerization Domain In Dape Enzymes Is Required For Catalysis, Boguslaw Nocek, Anna Starus, Magdalena Makowska-Grzyska, Blanca Gutierrez, Stephen Sanchez, Robert Jedrzejczak, Jamey C. Mack, Kenneth W. Olsen, Andrzej Joachimiak, Richard C. Holz
Chemistry: Faculty Publications and Other Works
The emergence of antibiotic-resistant bacterial strains underscores the importance of identifying new drug targets and developing new antimicrobial compounds. Lysine and meso-diaminopimelic acid are essential for protein production and bacterial peptidoglycan cell wall remodeling and are synthesized in bacteria by enzymes encoded within dap operon. Thereforedap enzymes may serve as excellent targets for developing a new class of antimicrobial agents. The dapE-encoded N-succinyl-L,L-diaminopimelic acid desuccinylase (DapE) convertsN-succinyl-L,L-diaminopimelic acid to L,L-diaminopimelic acid and succinate. The enzyme is composed of catalytic and dimerization domains, and belongs to the M20 peptidase family. To understand the specific role …
Selective Catalytic Oxidation Of Organic Sulfides By Iron (Iii) Porphryin Catalysts And Generation Of Iron (Iv)-Oxo Prophyrin Radical Cations, Nawras A. Asiri
Selective Catalytic Oxidation Of Organic Sulfides By Iron (Iii) Porphryin Catalysts And Generation Of Iron (Iv)-Oxo Prophyrin Radical Cations, Nawras A. Asiri
Masters Theses & Specialist Projects
Macrocyclic ligand-complexed transition metal-oxo intermediates are the active oxidizing species in a variety of important biological and catalytic oxidation reactions. Many transition metal catalysts have been designed to mimic the predominant oxidation catalysts in nature, namely the cytochrome P450 enzymes. Iron porphyrin complexes have been the center of research as catalysts. In this study 5,10,15,20- tetramesitylporphyrin (H2TMP) and its corresponding iron complexes FeIII(X)TMP (X= Cl, ClO4, ClO3, NO3, NO2, and BrO3) have been successfully synthesized and fully characterized by UV-vis and NMR spectroscopies. For the catalytic …
Unraveling The Activation Mechanism Of The Potato Tuber Adp-Glucose Pyrophosphorylase, Carlos M. Figueroa, Misty L. Kuhn, Christine A. Falaschetti, Ligin Solamen, Kenneth W. Olsen, Miguel Ballicora, Alberto A. Iglesias
Unraveling The Activation Mechanism Of The Potato Tuber Adp-Glucose Pyrophosphorylase, Carlos M. Figueroa, Misty L. Kuhn, Christine A. Falaschetti, Ligin Solamen, Kenneth W. Olsen, Miguel Ballicora, Alberto A. Iglesias
Chemistry: Faculty Publications and Other Works
ADP-glucose pyrophosphorylase regulates the synthesis of glycogen in bacteria and of starch in plants. The enzyme from plants is mainly activated by 3-phosphoglycerate and is a heterotetramer comprising two small and two large subunits. Here, we found that two highly conserved residues are critical for triggering the activation of the potato tuber ADP-glucose pyrophosphorylase, as shown by site-directed mutagenesis. Mutations in the small subunit, which bears the catalytic function in this potato tuber form, had a more dramatic effect on disrupting the allosteric activation than those introduced in the large subunit, which is mainly modulatory. Our results strongly agree with …
Kinetic And Spectroscopic Studies Of Bicupin Oxalate Oxidase And Putative Active Site Mutants, Ellen W. Moomaw, Eric Hoffer, Patricia Moussatche, John C. Salerno
Kinetic And Spectroscopic Studies Of Bicupin Oxalate Oxidase And Putative Active Site Mutants, Ellen W. Moomaw, Eric Hoffer, Patricia Moussatche, John C. Salerno
Faculty and Research Publications
Ceriporiopsis subvermispora oxalate oxidase (CsOxOx) is the first bicupin enzyme identified that catalyzes manganese-dependent oxidation of oxalate. In previous work, we have shown that the dominant contribution to catalysis comes from the monoprotonated form of oxalate binding to a form of the enzyme in which an active site carboxylic acid residue must be unprotonated. CsOxOx shares greatest sequence homology with bicupin microbial oxalate decarboxylases (OxDC) and the 241-244DASN region of the N-terminal Mn binding domain of CsOxOx is analogous to the lid region of OxDC that has been shown to determine reaction specificity. We have prepared a series of CsOxOx …
Inhibition Of Cysteine Protease By Platinum (Ii) Diamine Complexes, Chaitanya Rapolu
Inhibition Of Cysteine Protease By Platinum (Ii) Diamine Complexes, Chaitanya Rapolu
Masters Theses & Specialist Projects
Chemotherapy is the first line of treatment used in cancer. Chemotherapy drugs such as cisplatin, carboplatin and oxaliplatin are used in treatment. Cisplatin enters the cell through copper transporter CTR1 by passive diffusion and bind to DNA and proteins. Cisplatin is found to inhibit several enzymes targeting cysteine, histidine and methionine residues, which are expected to be responsible for its anticancer activity. A better understanding of how the size and shape and leaving ligands of platinum complexes affect cysteine protease, papain enzyme are studied. This could give new ways to optimize anticancer activity. The activity of papain enzyme was measured …
Patterning High Surface Area Silica With Lysozyme: Adsorption Kinetics, Fluorescence Quenching, And Protein Readsorption Studies To Evaluate The Templated Surface, Rachel M. Greer, Brittni A. Scruggs, R Alan May, Bert D. Chandler
Patterning High Surface Area Silica With Lysozyme: Adsorption Kinetics, Fluorescence Quenching, And Protein Readsorption Studies To Evaluate The Templated Surface, Rachel M. Greer, Brittni A. Scruggs, R Alan May, Bert D. Chandler
Chemistry Faculty Research
A method was developed for using an inexpensive and widely available protein, hen egg white lysozyme, as a patterning agent for commercial high surface area silicas. The basic patterning methodology involved spontaneous adsorption of the protein from aqueous solution, alkylation of the uncovered surface with an alkylsiloxane, and protein desorption in a slightly alkaline solution of morpholine. Adsorption kinetic studies using Bradford assays assisted in determining protein deposition conditions. These studies were generally consistent with results on more planar silica surfaces and indicated that the protein quickly and strongly adsorbs along its long axis at low surface coverages. A modified …
Eliminating Absorbing Interference Using The H-Point Standard Addition Method: Case Of Griess Assay In The Presence Of Interferent Heme Enzymes Such As Nos, Perera N. Indika, Mekki Bayachou
Eliminating Absorbing Interference Using The H-Point Standard Addition Method: Case Of Griess Assay In The Presence Of Interferent Heme Enzymes Such As Nos, Perera N. Indika, Mekki Bayachou
Chemistry Faculty Publications
Standard calibration methods used to determine trace analytes usually yield significant deviations from the actual analyte value in the presence of interferents in the assay media. These deviations become of particular concern when the concentration of the analyte is low, and when the results are used to draw mechanistic or kinetic conclusions, for instance in enzyme structure-function studies. In these circumstances, the H-point standard addition method (HPSAM) provides superior precision and accuracy. This method is developed here for the case of the spectrophotometric Griess assay used to determine nitrite in various enzymology investigations, such as nitrite determination in studies of …